Orochernes ganziensis, Gao & Zhang, 2019

Gao, Zhizhong & Zhang, Feng, 2019, First record of the genus Orochernes (Pseudoscorpiones: Chernetidae) from China, with description of a new species, Zootaxa 4612 (1), pp. 126-132 : 127-131

Orochernes ganziensis sp. n.

( Figs. 1–3 )

urn:lsid:zoobank.org:act:AF5E4A38-D890-4574-B2F8-673F092CDC86

Type material. Holotype male (Ps.- MHBU-SC10060401 ), China: Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Yajiang County [30°03.442′N, 101°46.339′E], elev. 3899 m, 4 June 2016, Xiangbo Guo leg. Paratypes: 5 males (Ps.- MHBU-SC10060402-06 ) , 7 females (Ps.- MHBU-SC10060407-13 ), same data as holotype .

Other material examined: 2 females (Ps. - MHBU-SC10060414-15 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Daocheng County [28.427°N, 100.352°E], elev. 4096 m, 10 June 2016, Xiangbo Guo leg. ; 1 male (Ps. - MHBU-SC10060416 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Xiangcheng County [29.134°N, 99.585°E], elev. 3258 m, 15 June 2016, Xiangbo Guo leg. ; 1 male (Ps. - MHBU-SC10060417 ), 13 fe- males ( Ps. - MHBU-SC10060418-30 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Batang County [30.380°N, 99.280°E], elev. 3215 m, 17 June 2016, Xiangbo Guo leg. ; 1 male (Ps. - MHBU-SC10060431 ), 2 fe- males ( Ps. - MHBU-SC10060432-33 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Baiyu County [30.572°N, 99.204°E], elev. 3850 m, 17 June 2016, Xiangbo Guo leg. ; 2 males ( Ps. - MHBU-SC10060434-35 ) , 2 females (Ps. - MHBU-SC10060436-37 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Seda County [31.767°N, 100.755°E], elev. 3918 m, 22 June 2016, Xiangbo Guo leg. ; 2 females (Ps. - MHBU-SC10060438-39 ), Sichuan Province, Ganzi Tibetan Autonomous Prefecture , Luhuo County [31.667°N, 100.707°E], elev. 3579 m, 23 June 2016, Xiangbo Guo leg.

Etymology. The specific name refers to the type locality.

Diagnosis. This species is recognized by the following combination of characters: eyespots present, tibia of leg I thickened and S-shaped, spermathecae with two short tubules, each with an enlarged round terminal bulb; trichobothrium st situated midway between sb and t; accessory teeth present on both chelal fingers, rallum with three blades; tarsus of leg IV with one tactile seta.

Description (holotype and all male paratypes, adults). Colour mostly dark brown, carapace, legs, tergites and pedipalps darker, remaining parts (sternites and pleural membranes) yellowish brown. Most setae clavate and slightly apically denticulate. Integument very dense and quite granular

Carapace. Surface evenly granular. Slightly longer than broad (1.06–1.08 ×), eyespots present, with two regularly granular transverse furrows, both of them distinct; the subbasal one slightly nearer to the posterior margin than to median furrow. With about 100 setae, including four on anterior margin and 12–13 on posterior margin. All setae short and apically dentate.

Coxal region. Manducatory process with two setae. Coxae of pedipalps slightly scale-shaped sculpture, coxae I with about 15, II 20, III about 19 setae, IV numerous setae.

Abdomen. All tergites widely divided except the tergite XI, with weakly scale-shaped sculpturing. Each halftergite with about 7–11 setae, tergite XI as in Fig. 3k , anus cone with two simple and acuminate setae. All sternites distinctly divided except last one, weakly scaly sculptured, setae simple and acuminate, half-sternites with about 7–10 setae, sternite XI as in Fig. 3l .

Genitalia. Male typical of Chernetidae , anterior genital operculum with 35–39 simple and acuminate setae, 16–18 setae in a row along the posterior margin of the posterior operculum.

Chelicera ( Figs. 3 a–c). With weakly scale-shaped sculpturing. Hand with 5 setae, all of them simple and acuminate except seta s bs which is apically dentate ( Fig. 3a ); with two lyrifissures on dorsal face of palm; fixed finger with 1–3 different sized distal teeth. Movable finger with 1, or occasionally 2 subdistal setae; serrula exterior with 17 lamellae. Rallum with three blades, anterior blade slightly denticulate ( Fig. 3b ). Galea with four short branches in distal or sub-distal position ( Fig. 3c ).

Pedipalps ( Figs. 2 b–c, 3d–f). Pedipalp slender, all surfaces granulate except chelal fingers which are smooth but not gaping; setae clavate and weakly apically dentate; without tactile setae on femur, patella or hand; trochanter with regular rounded dorsal hump; proportions: trochanter 1.38–1.55 ×; femur 2.91–3.10 ×; patella 2.64–2.68 ×; chela with pedicel 4.15–4.24 ×, chela without pedicel 3.85–3.96 ×, hand with pedicel 2.19–2.28 ×, without pedicel 1.85–1.92 × as long as broad. Movable finger 0.49–0.52 × as long as chela with pedicel, and 0.53–0.56 × as long as chela without pedicel. Fixed finger with 36–37 teeth, 4–5 acuminate accessory teeth on prolateral side, 4–5 accessory teeth on retrolateral side; movable finger with 40–44 teeth, 2–3 acuminate accessory teeth on prolateral side, 1–2 accessory teeth on retrolateral side. Venom apparatus present in moveable chelal finger only, venom duct slender, terminating in nodus ramosus slightly basal to trichobothrium t. Trichobothrial pattern as in Figs. 3 e–f: fixed chelal finger with eight trichobothria, movable chelal finger with four trichobothria: eb situated basally, est situated slightly closer to esb than to et, esb, ib and isb situated subbasally, almost at same level; est and ist situated submedially, ist situated midway of it and ib; t situated submedially, st situated slightly closer to sb than to t, distance between tip of finger and it slightly longer than that between ist and isb.

Legs: with weak scale-like sculpturing; subterminal tarsal seta simple, acuminate and curved; arolia undivided and shorter than claws; claws simple. Leg I ( Figs. 2d, 2g , 3h ) with Typical typical facies apart from tibia which is thickened, curved and S-shaped, with short, straight and toothed setae, and numerous sensory pores on dorsal side ( Figs. 2d , 3h ); other segments with numerous slightly denticulate and acuminate setae in germinal position, tactile setae absent, proportions: trochanter 1.17–1.25 ×; femur 1.57–1.69 ×; patella 2.62–2.75 ×; tibia 2.71–3.08 ×; tarsus 3.00–3.25 × as long as deep. Leg IV ( Figs. 2h , 3i ) with numerous clavate, terminal slightly denticulate setae, trochanter 2.08–2.36 ×; femur +patella 3.38–3.53 ×; tibia 4.20–4.40 ×; tarsus 4.00–4.29 × as long as deep, with one tactile seta (TS=0.69) ( Fig. 3j ).

Measurements (length/width or depth for leg I and IV).

Body length 2.04–2.43. Carapace 0.68/0.63–0.64. Pedipalp: trochanter 0.33–0.34/0.22–0.24; femur 0.64– 0.65/0.21–0.22; patella 0.58–0.59/0.22; chela (with pedicel) 1.06–1.08/0.25–0.26; chela (without pedicel) 0.99– 1.00; hand length (with pedicel) 0.57; hand length (without pedicel) 0.48; movable finger length 0.52–0.56. Leg I: trochanter 0.14–0.15/0.12; femur 0.22/0.13–0.14; patella 0.33–0.34/0.12–0.13; tibia 0.37–0.38/0.12–0.14; tarsus 0.24–0.26/0.08. Leg IV: trochanter 0.25–0.26/0.11–0.12; femur + patella 0.53–0.54/0.15–0.16; tibia 0.42–0.44/0.10; tarsus 0.30–0.32/0.07–0.08.

Short description of female paratypes. Mostly same as males, colour slightly lighter, carapace length approximately equal to breadth or slightly longer than broad (0.99–1.06 ×). Galea with five short terminal branches. Female genitalia: anterior genital operculum with 14–16 simple and acuminate setae, 10–13 setae in a row along the posterior margin of the posterior operculum ( Fig. 2f ). Spermathecae ( Fig. 3g ) with two short tubules, each with a distinct terminal bulb; egg capsule ( Fig. 2i ) with 7–11 embryos.

Proportions of pedipalp: trochanter 1.50–1.59 ×; femur 3.05–3.15 ×; patella 2.43–2.55 ×; chela with pedicel 3.75–3.86 ×, chela without pedicel 3.46–3.54 ×, hand with pedicel 2.00–2.07 ×, without pedicel 1.75 × as long as broad. Movable finger 0.49–0.50 × as long as chela with pedicel, and 0.54 × without pedicel.

Legs: leg I: trochanter 1.00–1.17 ×; femur 1.54–1.62 ×; patella 2.58–2.67 ×; tibia 3.33–3.44 ×; tarsus 4.17–4.50 × as long as deep. Leg IV: trochanter 2.25–2.45 ×; femur + patella 3.50–3.86 ×; tibia 4.20–4.40 ×; tarsus 4.00–4.14 × as long as deep.

Measurements (length/width or depth for leg I and IV).

Body length 2.50–2.73. Carapace 0.67–0.68/0.64–0.68. Pedipalp: trochanter 0.33–0.35/0.22; femur 0.63– 0.64/0.20–0.21; patella 0.56/0.22–0.23; chela (with pedicel) 1.05–1.08/0.28; chela (without pedicel) 0.97–0.99; hand length (with pedicel) 0.56–0.58; hand length (without pedicel) 0.49; movable finger length 0.52–0.53. Leg I: trochanter 0.12–0.14/0.12; femur 0.20–0.21/0.13; patella 0.31–0.32/0.12; tibia 0.30–0.31/0.09; tarsus 0.25– 0.27/0.06. Leg IV: trochanter 0.27/0.11–0.12; femur + patella 0.54–0.56/0.14–0.16; tibia 0.42–0.44/0.10; tarsus 0.28–0.29/0.07.

Molecular characters. One mitochondrial gene fragment (COI) and two nuclear fragments (18S rRNA and 28S rRNA) are deposited in GenBank, accession numbers MH479139 , MH479137 and MH479138 , respectively.

Distribution. China (Sichuan).

Remarks. This species most closely resembles O. sibiricus Schawaller, 1986 , but differs from the latter by the presence of accessory teeth on the pedipalpal fingers, and by having a slightly slenderer pedipalp (e.g. femur 2.91–3.10 × vs 2.70 ×, patella 2.64–2.68 × vs 2.30 ×) ( Schawaller, 1986). It can be distinguished from O. nepalensis by the presence of eyespots and by the stouter pedipalps (e.g. femur 2.91–3.10 × vs 3.90 ×, patella 2.64–2.68 × vs 3.10–3.20 ×) ( Beier, 1968). It differs from the both congeners by the presence of sensory spots on dorsal face of tibia I ( Figs. 2d , 3h )

Although all specimens have the usual single seta situate subdistally on the cheliceral movable finger, one male paratype (Ps.-MHBU-SC10060402) has two setae, with the additional seta indicated by the arrow in Fig. 3a .

Figures

FIGURE 1. Orochernes ganziensis sp. n., habitus, dorsal view: a. male holotype; b. female paratype.

FIGURE 2. Orochernes ganziensis sp. n., male holotype (a–e, g–h, j) and female paratype (f, i): a. carapace, dorsal view; b. left chela, prolateral view; c. left pedipalp, dorsal view; d. tibia of leg I, retrolateral view; e. male genital operculum, ventral view; f. female genital operculum, ventral view; g. leg I, retrolateral view; h. leg IV, retrolateral view; i. eggs (embryos), ventral view; j. tarsus of leg IV, retrolateral view. Scale bars: 0.20 mm.

FIGURE 3. Orochernes ganziensis sp. n., male holotype (a–f, h–l): a. chelicera, dorsal view; b. rallum; c. galea; d. left pedipalp without chela, dorsal view; e. left pedipalpal chela, prolateral view; f. distal part of left pedipalpal chela, retrolateral view; g. spermathecae; h. leg I, retrolateral view; i. leg IV, retrolateral view; j. tarsus of leg IV, retrolateral view; k. tergite XII, dorsal view; l. sternite XII, ventral view. Scale bars: 0.05 mm (a–c); 0.25 mm (d–l).